948 



THE NERVE SYSTEM 



much attenuated tail. The large, thick head projects into the anterior cornu, while 

 its thinner tail is prolonged caudolaterad, separated from the thalamus by the narrow 

 taenia semicircularis. Following the curved contour of the ventricle it is prolonged 

 as a narrow gray band in the roof of the middle cornu, where it joins the amyg- 

 daline nucleus. The nonventricular or capsular surface is embedded in the white 

 substance of the cerebral hemisphere, and is chiefly related to the internal capsule 



Fi<:. 702. The basal ganglia and thalamus schematically represented in a supposedly transparent 

 brain (right side); on the left is shown the outline of the lateral ventricle. 



The ventricular surface shows, in microscopic sections, a dense ependymal 

 lining. The capsular face is not sharply outlined, numerous strands of fibres, 

 to and from the internal capsule, entering it obliquely so as to appear as streaks 

 which extend to about the middle of the ganglion, there separating into finer 

 and finer strands which become lost to the naked eye. 



The lenticular nucleus (lenticula) (Figs. 701 and 702) is wholly embedded in the 

 white substance, and must be studied in sections. In its shape it resembles an 

 irregular triangular pyramid with its convex base directed laterad and parallel with 

 and near to the cortical expanse of the island of Ileil and of about the same extent. 

 Its ental, apical portion is directed toward the interval between caudate nucleus 



